악골에 발생한 악성 섬유성조직구종 2례

정종철,최홍란,오희균,박준아,류선열,이종호,김영운,정숭룡 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.3

Malignant fibrous histiocytoma rarely occurs in the jaws. Although the histogenesis of this tumor remains controversal, it is best regarded as a primitive and pleomorphic nature reflected by collagen production and occasional phagocytosis. It is common for metastatic foci to appear in lung and regional lymph node. There are variable treatments such as radiotherapy, surgical excision or combination, therapy of surgical excision, chemotherapy and radiotherapy. With the review of literatures, the authors report the clinical study of two cases of malignant fibrous histiocytoma of the jaw.

MPEG-2 변환부호기의 결합양자화 모델 설계

문철하,홍성훈 전남대학교 전자통신기술연구소 2002 전자통신기술논문지 Vol.5 No.1

Numerous applications for video transmission and storage are being developed based on the MPEG-2 video coding standard. Applications such as VoD, trick-play track on digital VTR's and extended-play recoding on VTR's motivate the idea of MPEG video transcoding. In general, by using the requantization, MPEG video transcoder reduces the bit-rate of incoming bit stream to the lower bit rate to meet the bandwidth of output links. In this paper, we investigates the requantization characteristics for MPEG-2 transcoding and it is shown that requantization effects produce the irregular size of decision intervals. From the investigation, we design the joint quantiation model with the same characteristics as the combination of quantization in encoder and requantization in transcoder. The simulation results show that the joint quantiation model is corrected.

국내 노상토의 M_R특성 분석을 위한 실험적 연구

문홍득,신영철 진주산업대학교 1997 산업과학기술연구소보 Vol.- No.4

The deflection and deterioration of road surfaces are largely related to the deformation of underlying soils. The American Association of State Highways and Transportation Officials(AASHTO) has adopted use of resilient modulus in the pavement design to represent the deformational characteristics of pavement materials due to repeated loading. Because of the recent interest in the use of resilient modulus for pavement design, it is needed to evaluate on the effects of moisture, soil type, and stress state on resilient modulus. In this paper, resilient characteristics are investigated for subgrade soils gained from road construction sites in Korea. The experimental technique basically follows the method suggested in this study.

건물내 라이프라인 배관의 내진성 향상을 위한 설계방법

辛太明,申澈洙,李洪西 충주대 2003 産業科學論文集 Vol.11 No.-

This paper emphasizer that seismic design of lifeline piping is necessary to avoid a secondary damage from earthquake like building fire. A large portion fo damage from the large historical earthquakes has been suffered surprisingly by post-earthquake fire. And it is well known that the fire had been caused by the failure of energy supply piping such as electricity pipes of gas pipes, of by the absence of rabid countermeasure system from failure of fire fighting equipment and water supply pipes. In this paper, it is discussed about a general seismic design method of building internal structure like lifeline piping and about a measure for reducing the seismic respones. As conclusions, it is proposed that lifeline piping should be simultaneously considered in the seismic design of building of importance for higher reliability.

결절성 및 괴상성 간세포암에서 역동적 전산화단층촬영 소견에 따른 경동맥화학색전술결과의 예측

이성문,김홍,지성우,우성구,이정형,서수지,손철호 啓明大學校 醫科大學 1997 계명의대학술지 Vol.16 No.2

Purpose: To evaluate retrospectively whether it is possible to predict the transarterial chemoembolization(TACE) result with the pre-TACE dynamic CT findings. Materials and Methods: The dynamic CT findings of 33 patients with 35 nodular and 8 massive hepatocellular carcinoma(HCCs) who was taken follow up CT after TACE, were reviewed retrospectively. After excluding the diffuse or infiltrative HCCs, the mass was classified into two groups of nodular and massive types. The size, location, degree of enhancement, pseudocapsule, portal vein(PV) thrombosis and arterioportal(AP) shunt were evaluated on the dynamic CT scans. The vascularity, multiple or parasitic blood supply, AP shunt and the possibility of superselection were considered on the angiography. After TACE, the pattern of lipiodol uptake and residual enhancing nodules were evaluated on the follow-up CT scans. Results: The good TACE results could be obtained in 18 of 35 nodular HCCs with dynamic CT findings of small size(mean=2.94cm), peripheral location, hyper-or iso-enhancement, and absence fo PV thrombosis, with angiographic finding of possible superselection, but the pseudocapsule did not give important effect on the result. Most of the massive HCCs had poor TACE results. Conclusion: The prediction of the TACE results of nodular and massive HCCs was possible with dynamic CT findings. If the good prognostic factors were not observed on the pre-TACE dynamic CT, the multiple TACE and/or combination therapy with percutaneous ethanol injection(PEI), surgical resection or others should be considered for the effective control of the HCCs.

도마 Yeo2동작에 대한 운동학적 요인 분석

윤희중,여홍철,김태삼 한국운동역학회 2001 한국운동역학회지 Vol.11 No.1

The purpose of this study was to investigate the effect of the kinematic factors about event of the Yeo2 motion on the Horse Vault. The subject in this study was 1 male gymnast to performance Yeo2 motion. Two video cameras were used to attain kinematic variables by phase. As a result, the following conclusion was drawn; 1. As the take-off time on the board was short, it appeared to increase horizontal and vertical velocity. In the motion, the flight apex height increased largely, too. 2. As the contact time on the board was short, it appeared to performance the air motion smoothly by increasing the horizontal distance and apex height. 3. The horizontal and vertical velocity in take-off on the board appeared increase horizontal distance and apex height. 4. To increase the apex height and horizontal distance, the body appeared to must be take the posture of vertical axis in take-off on the board.

두부외상환자에서의 예후인자

최성혁,문준동,김수진,문철규,이성우,홍윤식 대한응급의학회 2001 대한응급의학회지 Vol.12 No.2

Background: Predicting outcome after head trauma is of great interest for clinicians, especially in the early stage. It may provide a basis for therapeutic strategies and may be helpful to select different approaches. But, reliable outcome prediction from head trauma is still unresolved. The purpose of this study is to determine which clinical parameters can be used effectively after an event of head trauma. Methods: In our study we studied head trauma patients who came to the Emergency department of Korea University Medical School Anam Hospital from the 1st of June 1998 to 31th of January 2000, looked into medical records, and studied the records in a retrospective manner. The head trauma patients were divied into two group, a) favourable outcome-related and b) unfavourable outcome-related. The two groups were then subdivided according to their sex, age, the mechanism of their injury, the time they came in, alcohol drinking, loss of consciousness, vomiting, pupil change, previous medical illness, associated injuries and were seperately compared and analyzed. And the factors affecting Glasgow Outcome Scale(GOS) were analyzed in the parameters of Injury Severity Score(ISS), Revised Trauma Score(RTS), Glasgow Coma Scale(GCS), motor score of GCS(mGCS), Marshall Computed Tomographic Classification(MCTC). Statistically, t-test and Mann-Whistney rank sum test using Jandel-sigma were used in the study and then were assessed in Chi-square analysis methods. The statistical significance was determined at a level of p less than 0.05. Results: The total of the head trauma patients, added up to 129 people, 99:males and 30:females. Among this sum, 99 patients showed a favourable outcome and 30 patients showed an unfavourable outcome at discharge. The causes of injury included: automobile accident in 42 cases; fallss in 26; assaults in 6; and accidental-slipping injury etc in 55 cases. 12 patients had bilateral unreactive pupils on admission, 2 had unilateral reactive pupils, and 113 had bilateral reactive pupils. Compared to the favourable outcome-related head trauma group, the unfavourable outcome-relared head trauma group had more history of loss of consciousness, unreactive pupils and tended to have previous medical illness. There were no difference in alcohol related, vomiting and associated injuries between two groups(favourable outcome-related head trauma group: unfavourable outcome-related head trauma group). Substantial difference were observed in GCS, mGCS, ISS, RTS, MCTC between two groups. Patients with unfavourable outcome had a significantly higher ISS, lower RTS, lower mGCS. After MCTC, patients with mass lesion had unfavourable outcome than patients with diffuse injury. Conclusion: Age, history of loss of consciousness, previous medical illness and unreactive pupil change are predictives of outcomes of head trauma patients with respect to Glasgow outcome scale. The lower GCS, lower RTS, lower mGCS, higher ISS, mass lesion based on CT scan provide poorer prognostic outcome in patients with head trauma. Use of prognostic factors thorough complete history taking and physical examination would provide useful prognostic information and facilitate improved therapeutic decision-malting in head-injuried patients.

굴패각을 충진제로 이용하는 생물학적 오수처리방안 연구

김종오,최연돈,김홍철 경상대학교 생산기술연구소 2000 生産技術硏究所論文集 Vol.16 No.-

The purpose of this study was to develope the economical sewage treatment technology using oyster shells as biological contact media. As the stage of feasibility test in laboratory scale, the new submerged media processes with media-filling ratios of 20% and 55% were compared with the conventional activated process. Comparison parameters were the performance characteristics such as organic, nitrogen, phosphorus removal efficiencies. Operating conditions in terms of hydraulic retention time varied at 12 hr, 10 hr, and 8 hr. The results were as follows; 1.Removal efficiencies of organics such as BOD and COD showed almost the same in activated sludge and submerged oyster shell processes. The different filling ratios in submerged process showed also the same organic removal characteristics. 2.Nitrogen removal efficiencies showed that the submerged oyster shell process were better than activated sludge process. However, the different filling ratios in submerged process showed almost the same nitrogen removal characteristics. 3.Phosphorus removal efficiencies showed almost the same in activated sludge and submerged oyster shell processes. The increasing filling ratios in submerged process showed the little improvement of phosphorus removal efficiency.

음주 외상 환자

이성우,문준동,최성혁,문철규,홍윤식 大韓應急醫學會 1999 대한응급의학회지 Vol.10 No.2

Background: We studied the incidence of trauma caused by alcohol related accidents, and the effects that alcohol has on the occurrence, the extent, and the outcome to the patient. Methods: In our study we studied trauma patients excluding pediatric patients(15 years old and under) who came to the Emergency department of Korea University Medical School Anam Hospital from the 1st of January 1996 to 30th of June 1996, looked into their medical records, and studied the records in a retrospective manner. The trauma patients were devided into two groups, a) alcohol-related and b) alcohol-non-related. The two groups were then subdivided according to their sex, age, the time they came in, the anatomical part of the trauma, the mechanism of their injury, the extent of the injury, the length of their hospital stay, the length of their ED stay and were seperately compared and analyzed. Statistically, ANOVA and logistic regression analysis using SAS were used in the study and then was assessed in Chi-square analysis methods. Results: The total of the trauma patients, added up to 832 people, 577:male and 255:female. Among this sum, 163 trauma patients were alcohol related(male:127 & female:36). 115 people were in the age group of 21-40. Compared to the non-alcohol related trauma group, the alcohol-related group had more facial & scalp injuries and tended to come in the hours between 0-6 AM. The cause of the injuries were mostly by fist-fighting and suicide, compared to mostly accidental-slipping injuries in the non alcohol-related group. There were no difference in the degree of the injury(ISS) and the length of hospital stay between the two groups, whereas the length of the stay at the ED was longer to the alcohol-related trauma patients. Conclusion: Alcohol related trauma patients were mostly in their 20s and 30s, came to the hospital at a late time and the reason for their visit were mostly because of fist fighting. In the Emergency department, because prompt and correct diagnosis is quite difficult to make in this group, their ED stay tended to be longer. We can conclude that measuring the blood alcohol level of these patients, continuing the psychological therapy and educating people is needed.

Effect of LiBiO2 on low-temperature sintering of PZT-PZNN ceramics

Hong Sung Cheul,Kim Shi Yeon,Yeo Dong-Hun,Shin Hyo-Soon,Park Zee Hoon,남산 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.5

In this study, the sintering characteristics of 0.69Pb(Zr 0.47 Ti 0.53 )O 3 -0.31Pb[(Zn 0.4 Ni 0.6 ) 1/3 Nb 2/3 ] (PZT-PZNN) ceramics after the addition of LiBiO 2 were studied. This addition lowered the sintering temperature from 1150 to 900 °C. The crystal structure changed from tetragonal to rhombohedral as the additive content increased by 0.7%. The polarization of the sintered specimen was conducted at an electric fi eld of 3 kV/mm. When 0.7 wt% of LiBiO 2 was added and sintered at 900 °C, the piezoelectric constant ( d 33 ) was 602 pC/N; moreover, the electromechanical coupling coefficient ( k P ), sintered density, and Curie temperature ( T c ) at 1 kHz were 66.3%, 7.99 g/cm 3 , and 252.8 °C, respectively. When 0.7 wt% of LiBiO 2 was added, the PZT-PZNN ceramic showed an increased strain curve of 0.118% at 2 kV/mm. The interdiffusion between the copper (Cu) electrode and ceramic material was not observed in the scanning electron microscopy (SEM) results; thus, the possibility of manufacturing an actuator using a Cu electrode using a novel composition was confirmed. The actuator displacement with the voltage 400 V was 1.2 μm. The thickness of the multi-layered actuator was 1 mm. Through this, the possibility of manufacturing a multi-layered actuator with a Cu electrode was confirmed through the composition of 0.69PZT-0.31PZNN (LiBiO 2 0.7 wt%).